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Home >> Mazda >> 2014 >> MX-5 Miata Club, Automatic Trans >> Repair and Diagnosis >> Engine Performance >> System >> Symptom Troubleshooting [Engine Control System] >> Engine Control System Operation Inspection >> Cooling Fan Control System Inspection
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Cooling Fan Control System Inspection

If simulation function of M-MDS is used: 

  1. Connect the M-MDS to the DLC-2.
  2. Start the engine and warm it up to normal operating temperature.
  3. Verify that the DTC P0480, P0481 or P0482 is not shown and cooling fan operating while the KOER self-test.orm the KOER self-test. (See KOEO/KOER SELF TEST ).
  4. Verify that the DTC P0480, P0481 or P0482 is not shown and cooling fan operating while the KOER self-test.
    • If the DTC P0480 is shown, perform the DTC troubleshooting procedure. (See DTC P0480 ). (See DTC P0481 ). (See DTC P0482 ).
    • If the cooling fans do not operate while KOER self-test, proceed the followings:
    1. Inspect the cooling fan motor and wiring harness between cooling fan motor and ground.
    2. Select the FAN1, FAN2 and FAN3 PIDs.
    3. Turn ignition switch off and disconnect the cooling fan motor connector.
    4. Verify that each cooling fan relay operating sound is heard, when turn each cooing fan relay to on from off using simulation function of the FAN1, FAN2 and FAN3 PIDs.
      • If the operation sound is not heard, inspect for suspected cooling fan relay is stuck open or close.
      • If the operation sound is heard, inspect wiring harness and connector between all cooling fan relays and cooling fan motor.

If simulation function of M-MDS is not used: 

  1. Connect the M-MDS to the DLC-2.
  2. Start the engine and warm it up to normal operating temperature.
  3. Perform the KOER self-test. (See KOEO/KOER SELF TEST ).
  4. Verify that the DTC P0480, P0481 or P0482 is not shown and cooling fan operating while the KOER self-test.
    • If the DTC P0480 is shown, perform the DTC troubleshooting procedure. (See DTC P0480 ). (See DTC P0481 ).

      (See DTC P0482 ).

    • If the cooling fans do not operate while KOER self-test, proceed the followings:
    1. Inspect the cooling fan motor and wiring harness between cooling fan motor and ground.
    2. Turn the ignition switch to off.
    3. Disconnect ECT sensor connector.
    4. Verify that the operation sound heard form all cooling fan relays (No. 1, No. 2 and No. 3), when the ignition switch to ON position.
      • If the operation sound is not heard, inspect for suspected cooling fan relay is stuck open or close.
      • If the operation sound is heard, inspect wiring harness and connector between all cooling fan relays and cooling fan motor.
    5. Turn the ignition switch off and disconnect the ECT sensor connector.
    6. Reconnect the ECT sensor and clear the DTC from PCM memory using the M-MDS. (See AFTER REPAIR PROCEDURE ).
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